What was found
DURING STRAIGHT AND LEVEL FLIGHT AT 3,700 FEET, TWO SHARP VIBRATIONS, EACH LASTING TWO SECONDS, APPROXIMATELY ONE SECOND APART WERE FELT IN THE AIRFRAME. A PRECAUTIONARY LANDING AT NEAREST PLATFORM WAS ACCOMPLISHED. DURING POST-FLIGHT INSPECTION, NOTICED INDIVIDUAL BEARING BALLS FROM THE NR 2 DRIVE SHAFT HANGER BEARING WERE NO LONGER IN THE BEARING ASSEMBLY. NOTIFIED MAINTENANCE. UNCONTAINED FAILURE OF FORWARD BEARING ON THE NR 2 SHAFT AND BLOWER ASSEMBLY.